Project Summary Devastating voice loss (dysphonia or aphonia) impacts thousands of individuals in the United States each year undergoing traumatic or oncologic partial laryngectomies, or suffering muscle volume loss due to vocal fold paralysis. Voice restoration options for these patients are suboptimal, and, as a result, most patients are left with permanent voice loss and communication impairment. This application introduces a novel approach for restoring vocal fold muscle volume and function after direct vocal fold injury and/or denervation. Results may lead to improved surgical options for voice restoration in patients who have vocal paralysis and/or have undergone hemilaryngectomies, cordectomies, or traumatic avulsions. The first goal of this application is to engineer an autologous muscle-cartilage implant progenitor cell-derived implant (MI) that, after implantation in an animal model, receives strong innervation and becomes functional when used to repair a large laryngeal defect. To do this, we will fabricate MIs within a customized collagen matrix and pre-treat MIs with factors in vitro that induce the MI muscle to express motor endplates. The MIs will be used to replace a partial laryngectomy defect in a porcine model, and post-implantation innervation status, based on laryngeal electromyography and quantification of motor endplates with nerve contact, will be determined. Using this animal implant model, outcomes with the study MIs will be compared to those of control MIs in environments with and without recurrent laryngeal nerve integrity. Findings from the proposed studies should overcome current major hurdles to developing a functional tissue engineered MCC for hemilaryngeal reconstruction?those hurdles being inadequate cartilaginous support, poor innervation of the muscle, suboptimal organization of myofibers, and asynchronous firing of the muscle with the native adductor muscle. Furthermore, because these studies are being done now in a large animal (porcine) model, with laryngeal size and function very similar to that of humans, findings will be highly translational. Results from these experiments should lead to landmark clinical innovations that will be relevant to both voice restoration applications, and muscle repair concepts globally.